It is known an ultrasound imaging system comprising:                an ultrasound probe comprising a plurality of transducers for emitting and receiving an ultrasound wave inside a medium, a received ultrasound wave being sensed by said transducers and being converted into input data by at least one analog to digital converter, and        a computer receiving said input data through a data channel and processing these input data to provide an image representing a portion of said medium.        
According to a first known embodiment, illustrated on the FIG. 1, a digital acquisition board (DAB), that is an interface board, is located between the ultrasound probe and the computer. Such interface board comprises a programmable logic device (PLD), usually a FPGA circuit, or a digital signal processor (DSP) for processing a beamforming process on at least a predetermined and limited number of signals. The beamformed data are then transmitted to the computer via a data channel.
In that case, the interface board comprises a predetermined and limited number of input signals, and the PLD or DSP has a limited computational power. If the number of transducers is increased, a new interface board must be designed, which is very expensive.
According to a second known embodiment, illustrated in the FIG. 2, the digital acquisition board (DAB) or interface board is located between the ultrasound probe and the computer. The interface board sends all the sensed signal samples (input data) to the computer by multiplexing them into a data channel.
Depending on the number of transducers, the data channels existing inside a standard computer are usually not able to absorb the input data rate from the transducers. Even though the data channels are efficient, the microprocessor of the computer is then unable to operate the beamforming process upon such a huge quantity of input data.